Dose dispensing apparatus

ABSTRACT

A dispensing system for controlled, especially remote controlled, dispensing of medicaments is disclosed. The system consists of a dispensing mechanism adapted to receive a sealed or resealable container of material to be dispensed and to validate that it is the correct material, and which includes a mechanical actuation mechanism which, when actuated, causes a measured dose of material to be dispensed from the material container. The mechanical actuation mechanism may be inhibited from operation by a locking mechanism which, when actuated, locks the device against the further dispensing of a dose of material until release in accordance with the desired dispensing programme, e.g. until a certain time period has elapsed, or until the programme permits dispensing to occur on some other basis. The dispensing system may be in two parts, a hand-held hand-actuated dispensing mechanism ( 1 ) and a base or docking station ( 2 ) into which the hand-held unit may be placed in order to release the locking mechanism. The docking or base station ( 2 ) may be triggered to cooperate with a remote overall control system, for example a remote computer, by placing the hand-held dispensing mechanism ( 1 ) in it.

RELATED APPLICATIONS

This application is a National Stage application of PCT InternationalApplication No. PCT/GB01/04689 filed, Oct. 22, 2001.

BACKGROUND OF INVENTION

This invention relates to dose dispensing apparatus, particularly thoughnot exclusively for dispensing doses of drugs and other likemedicaments. It can, however, be used in analogous areas wherecontrolled dispensing of material is desired. It is of particular valuefor dispensing measured doses of fluent medication from a storagecontainer containing a reservoir of such medication, although it canalso be used to dispense unit dosages of solids each as, for example,tablets.

Pharmaceutical packaging is normally designed to make access by thepatient easy and unrestricted. There are, however, situations whereconsiderations of safety and security make it necessary to control andrecord the usage of medicines by patients. Additionally, supervision ofdosage by medical, nursing and care staff is time-consuming and costly,particularly if the patient is not in hospital or other care facility.This is especially the case if the patient needs to take a combinationof medicines with a strict regime of medication. Also, while in the caseof many medicaments and pharmaceuticals the dosage regime may be subjectto wide variation without potential danger to the patient on the onehand or loss of effectiveness of the medication on the other, it is wellunderstood that medication is desirably effected using a regular dosageregime. It is found that this is not always easiest achieved simply byrelying on a patient to follow written instructions. Attempts haveaccordingly been made to develop devices which are themselvesessentially “programmed” to dispense medicament at the correctintervals, but such systems have tended to be of narrow applicabilityand complex and, indeed, to be easily defeated. Thus, suggestions havebeen made in the case of multiple pill-based medication regimes, toprovide automated dispensing devices. U.S. Pat. No. 5,752,621 and U.S.Pat. No. 5,472,113 both disclose apparatus which can be used todispense, at appropriate times, various pills in appropriatecombinations. Further prior art dispensing apparatus is referred to ineach of these specifications.

Devices for dispensing fluent materials such as drugs and medicamentsare known in a wide variety of forms. Generally they consist of acontainer which is sealed and from which a suitable dose of material maybe ejected. One particular widespread presentation for drugs,particularly the treatment of asthma, is that of a small pressurisedcanister having a valve at one end and a dispensing tube fitted with anozzle. So-called inhalers are well-known and widely used by asthmatics.In principle, however, such a presentation is not in any senserestricted to drugs for use in treating asthma, but can be used for awide variety of medicaments and pharmaceuticals. The mode ofadministration additionally does not always have to be by way of anaerosol spray. For example, it is entirely conceivable to dispense pastyor creamy formulations from a canister with some form of pump valve onit. Even discrete dosage forms such as pills may be presented incontainers from which pills may be released one at a time. This is aparticularly preferred dosage approach presentation for homeopathicremedies where it is believed highly desirable that the pill may betaken without being handled by the person taking it more than strictlynecessary. Alternatively, pills may be incorporated into a strip orribbon which may be fed out from a cassette or the like one by one, andreleased from the strip for administration.

A separate consideration in connection with the administration ofmedicaments arises in the case of controlled clinical trials, or even,though to a lesser extent, patient monitoring. It is particularlyimportant in a controlled clinical trial to ensure not only that thedosage regime is followed, but that a positive record is secured whichenables that to be verified. Any such system should, of course, not becapable of being falsified by the patient.

A further separate consideration which applies in some cases is thestrong desirability of avoiding overdosing. This can be of particularimportance in the case of medicaments used in diabetes treatment wherethey can have extremely adverse effects if not used in the rightquantity at the right time.

Yet a further problem which arises in connection with the controlledadministration of medicaments in unsupervised conditions is to ensurethat the right medicament is being administered, and in the case ofcontrolled or prescription medicines, that no diversion occurs.

SUMMARY OF INVENTION

We have now found that substantial advantages may be obtained, but incost-effective fashion, by providing improved dispensing systems whichenable a dose of medicament or the like to be dispensed from a sealed orsealable container in accordance with a pre-programmed regime and whichare so arranged that the regime must essentially be adhered to.

According generally to a first feature of the present invention, thereis provided a dispensing system consisting of a programmable dispensingmechanism adapted to receive a sealed or resealable container containingmultiple doses of material to be dispensed, and including a mechanicalactuation mechanism which, when actuated, causes a measured dose ofmaterial to be dispensed from the material container, and wherein themechanism may be inhibited from operation by a locking mechanism which,when actuated, locks the device against the further dispensing of a doseof material until released in accordance with a desired dispensingprogramme, and wherein the container and dispensing mechanism areprovided with means enabling the authenticity of the container placed inthe dispensing mechanism to be checked.

Such release may be effected, for example, merely by the passage ofsufficient time or, and this is generally preferred, by means of therelease of a suitable latching mechanism which acts to lock the deviceagainst dispensing until such release is effective. The latchingmechanism may be mechanical, electrical or electromechanical, but, inevery case, must be as a whole programmable with the desired dosageregime. The release may be effected by suitable actuation locally or byremote control.

Preferably the container has an identification tag associated therewithand containing information about its content, and the dispensingmechanism includes means for addressing the tag and validating thedosage regime in accordance with a preset programme. The tag may takethe form of a simple marking on the face of the container such as abarcode, or it may be a more sophisticated form of tag including dataabout the medicament and even being in the form of a “smart card” whichenables information not only to be extracted from the tag but alsowritten to the tag.

It is particularly preferred to provide a dispensing system in twoparts, one of which can be envisioned as a hand-held hand-actuateddispensing mechanism and the other as a base or docking station intowhich the hand-held unit may be placed in order to release the latch.Such a docking or base station may be more or less sophisticated and maybe self-standing, or alternatively it may operate in cooperation with aremote overall control system, for example a remote computer. In onespecific aspect of the present invention, the docking station maycontain transmitter/receiver means for communicating with a centralcontrol computer enabling exchange of signals/data between the remotecomputer and the base or docking station and accordingly, if thedispensing device is placed in the base or docking station, between theremote computer and the dispensing device. In such a system, it isentirely possible to arrange by means of suitable programming andsuitable easily implemented electronics that the dispensing history ofthe hand-held device can be uploaded to a central remote computer at thesame time or adjacent in time to the remote computer sending thehand-held device appropriate control signals.

The means of communication between a base or docking station and aremote computer can be any appropriate means, for example using cellulartelephony techniques, via the Internet or via any other appropriatecommunications mechanism.

It is also possible to provide, in the hand-held dispensing device,means for communicating with a separate standard computer device, forexample a personal computer, palm-top, PDA or WAP telephone. Byincluding an infra-red communications port in the hand-held device, oncecommunication is established by placing the device in or near thedocking station and actuating communication, a dialogue may beestablished between the patient and a host computer or even with aphysician or other adviser. Thus, it is possible, at the same time asdealing with the basic reporting of past use of the device, to enablethe patient to fill in a questionnaire, or to enter into the system aquery about their condition or a report of current state of health. This“telemedicine” aspect to the dispensing system of the present inventionprovides very substantial flexibility of communication between patientand doctor, and enhances clinical care opportunities.

In the case of clinical trials or similar procedures, operating in thisway enables a substantial degree of control and monitoring to be easilyand cost-effectively carried out without the ease of use of themedicament for the user or patient being compromised.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is illustrated by way of example with reference to theaccompanying drawings in which

FIG. 1 shows a drug dispensing unit and base station in accordance withthe present invention,

FIG. 2 shows the unit of FIG. 1 about to be used,

FIG. 3 shows an alternative general view of an alternative dispensingunit and base station,

FIG. 4 shows the unit of FIG. 3 in use, and

FIGS. 5 a and 5 b show in exploded view from front and back respectivelya third embodiment of a drug-dispensing unit and base station inaccordance with the invention.

DETAILED DESCRIPTION

Referring to the drawings, FIG. 1 shows a dispensing unit generallydenoted 1 which can be placed on top of a base unit generally denoted 2.The base unit is connected via a power and signal cable 3 withappropriate related apparatus, for example to a telephone socket or to aPC interface card. The upper face of the docking station 2 carries a rowof connector terminals 5 which can, when the dispensing unit 1 is placedon the docking station 2, electrically contact corresponding members(not shown in FIGS. 1 and 2) located on the underside of the dispensingunit 1.

The dispensing unit itself is provided with a liquid crystal displayscreen 10 and some function buttons 11, and has at its upper end anozzle actuation cap 12 with a lowerable closure tab 13 which can beused to cover an aerosol outlet 14 in cap 12, thus preventing theaerosol outlet being clogged with dust, dirt or other contamination.

Cap 12 may be releasable from the upper end of the main body of thedispensing device as shown in the drawings to enable a pressurisedcanister with a standardised outlet tube to be located within it, theoutlet tube being registered with an appropriate aerosol nozzle 14. Bypressing the cap 12 down into the main body of dispensing device 1, theaerosol valve may be actuated and a dose of material expelled,whereafter an electromechnical latch within the main body of thedispensing device 1 may act to prevent the cap 12 being pushed into thebody of dispensing device 1 a second time until release occurs. Releasemay occur merely following the passing of a given period of time, but itis highly desirable more positively to control the ability of the deviceto dispense. For this purpose, it is straightforward to arrange that thelatch within the main body of dispensing device 1 will remain locked toprevent a further depression of cap 12 until appropriate steps are takento release it. For example, release may be effected remotely inaccordance with a pre-programmed regime by placing the dispensing unit 1on to the base station 2 and thereafter having the dispensing stationand the base station communicate with one another, whereon, ifappropriate, the internal latching may be released. The status of thedispensing device 1 may be shown on screen 10, both before and afterplacing on the base station. A number of push buttons 11 are provided inorder to control input from the user, for example to enable the user toset up a communication link with the remote computer via the basestation 2.

Once such a link has been established and e.g. the latch released sothat a second dose may be dispensed,. the dispensing device 1 may beremoved from the base station, held in the hand as shown in FIG. 2, andthe cap again depressed in the direction of arrow 30 shown on FIG. 2. Itis easy to arrange that when such actuation occurs, the latch within thedispensing unit 1 re-engages to prevent a second dispensing action andseparately the status of dispensing unit may change, the change beingdisplayed in window 10.

Alternatively, the device may include suitable control circuitryinternally, such circuitry acting to release locking and enable afurther dose to be dispensed after a suitable period of time, andpreferably including a rewritable memory store to maintain a record ofwhen doses were in fact administered. The content of such a store may beautomatically transferred to a store in the docking station when thedevice is docked, or transferred direct to a remote computer if desired.

As shown in FIG. 1, the closure tab 13 which acts to shield ingress ofdirt into the dispensing outlet 14 has an angled out portion 20 whichcan be engaged by the forefinger of the left hand as shown in FIG. 2 ofthe drawings in order to achieve dispensing.

Such an approach is not always desirable, or, indeed, convenient, and itmay be particularly awkward for people with arthritis. Accordingly,FIGS. 3 and 4 show an alternative construction where dispensing isachieved by means of a lateral grip across a generally ovalcross-section elongate housing which covers the dispensing device.Referring to FIGS. 3 and 4, the system consists again basically of adocking station 21 connected via cable 28 and a squeezable dispensingunit 22. The latter has a display screen 23 in a slidable centralsection which can be slid up to reveal the nozzle of an aerosoldispensing nozzle 24 which is visible in FIG. 4, but not in FIG. 3.Likewise visible in FIG. 4 but not in FIG. 3 is the set of controlbuttons 25 which enable the unit to be controlled by the user.

The mechanical construction enabling a squeezing movement exerted asshown in FIG. 4 to be converted into an axial compression to release adose from a pressurised container via the aerosol nozzle may be simplyeffected using appropriate standard mechanical constructions, and themechanical arrangements for latching the device against an immediatesecond use can likewise be simply and appropriately constructed. Locatedwithin the housings of the respective dispensing devices 1 and 22 shownin FIGS. 1 and 3 respectively are also appropriate electronics and apower supply or back-up power supply, for example one or more batterycells. If desired, the electronics may be rechargeable and rechargingcan take place when the respective dispensing unit is located on itsdocking station 2 or 21. This can obviously be effected automatically byappropriate design and programming.

FIGS. 5 a and 5 b show a further embodiment of the dispensing system, ineach case in exploded view from front and back respectively. Referringto these figures, from which detail has been omitted for the sake ofclarity, the system consists of a base station 50 into which a hand-helddispenser can be set when needed. A contact pad 51 enables signals to besent to and from the hand-held unit when it is placed in base station50.

The hand-held unit consists basically of front and rear casing shells55,56 respectively which clip together round a circuit board 57 and aninternal moulded receptacle unit 58. Shown above unit 58 in the drawingis a removable cartridge housing 60 which may be locked into place inthe assembled housing or released therefrom as and when necessary.Cartridge housing 60 is designed to receive a container of medicament62, here in the form of an aerosol spray canister with a dispensingnozzle 64 which lies in the upper part of housing 60 which is suitablyconfigured to enable a dose of medicament to be dispensed sub-linguallyvia apertures 66.

Circuit board 57 bears a latch assembly 70 designed to interact withportions of housing 60 to enable the housing to be latched in place orremoved upwardly from the rest of the device. The latching assembly alsoallows, at appropriate intervals controlled by programming, the housing60 to be pushed down in the upper half of moulding 58 to enable a set ofpins 72 to press on the ends of the arms of a spider 74 and so cause thecontainer 62 to be pressed towards the nozzle 64, so dispensing a doseof medicament therefrom. After one (or if programmed appropriately more)such compressions, the latch assembly may lock the housing 60 againstfurther such movement until released when the next dose of medicament isdue to be dispensed. The exact nature of the operation of the spider 74and associated components is described in more detail in our copendingapplication filed on even date and claiming the priority of GB patentapplication 0025811.1.

Circuit board 57 carries a display screen 76 visible through a window 78in casing front 55. In use of the device, this screen cam carry amessage to the user, for example indicating the state of the device,ready to dispense or locked. Casing front 55 also has four apertures 80which, when the device is assembled, are filled with rubberypressbuttons (not shown in the drawing), which enable actuation of fourswitches 82 set in circuit board 57. The upper end 84 of board 57carries a printed RF antenna which enables the checking of a so-calledRF tag 86 which forms part of the cartridge assembly. This enables thesystem to check just what medicament has been loaded into it when afresh container 62 and associated tag 86 are inserted into the upperhousing 60 and that housing latched into position in moulding 58.

The hand-held unit may be powered by a suitable battery which can fit inthe area denoted 88 in the drawing.

It will be readily appreciated that using devices as shown in FIGS. 1, 4and 5 a/5 b, the degree of control of dosage can be very high and theease of recording and monitoring of the dosage regime is substantial.If, for example, the base station 2, 21 or 50 is connected into thenormal telephone system, a central controlling computer can monitor theoperation of the device by the user remotely, and any anomalous orundesired administration can be detected rapidly and appropriateimmediate action taken. A further advantage is that, for example, asounder is easily incorporated into the base unit which can beprogrammed by the central computer to emit an audible signal, e.g. toremind a user that dosage is overdue. The operating rules may providethat if within say 5 minutes of the emission of such an audible signalthe user does not acknowledge having heard it, an appropriate record canbe made of this event.

As noted above, the device may itself include appropriate controlcircuitry including a memory device. In such a case, it is possible toprogramme that circuitry (and a remote computer) so that when the deviceis first docked, it starts by establishing a communication link with theremote computer, which can then initially set-up′ the device withappropriate parameters for a patient. These could, for example, governthe length of a PIN No required to access the docking station anddetails of the proposed dosage regime, for example initially loading anexpected running average based on the prior doctor/patient experience.This false average could form the foundation for a continuing runningaverage that is calculated with time and use. This data would constitutea benchmark, enabling the device thereafter to monitor usage levels andto detect any incidence of deviation. The time and frequency of use, andother events such as opening of the casing or tampering with it, may bestored and uploaded to a central system as desired. The system may beprogrammed to issue restrictive orders on the patient's medication, orit may simply be programmed to report data, so as to highlight areas ofconcern and alert the appropriate GP or specialist for attention at thepatient's next appointment.

As noted above with reference to FIGS. 5 a/5 b, in place of orsupplementary to the downloading of data via a remote link, data may bestored with the container for the material to be dispensed. In someareas, there is already a requirement for a form of tagging on medicinalcanisters that can be read or written to. This tag carries informationas to the medication type, use-by dates, etc. and when used with adevice according to the present invention, the tag may be accessed bythe device (and/or via the docking station), and the device could beprogrammed to write to the tag the number of doses left in case ofremoval from the device. The tag could have a large memory capacity freefor other uses. On return of the canister to the pharmacist, the usagedata written to the canister can then be interrogated. Data as to whenthe canister was used and by whom, would remain with the canister ofmedication that was dispensed. This method of data management may proveto be more convenient and effective in some cases than online monitoringwith the device (including the canister) being mated with the dockingstation.

It can be seen that a wide variety of modifications may be made to theoverall general construction and design described above, many of themeasily made simply by changing computer programmes. Such changes couldbe made “online” when the hand-held unit is in the docking or basestation and in communication with a host computer. The system accordingto the invention is of particular value in the monitoring and analysisof administration during a controlled trial, enabling it to be highlyautomated and reliable. In particular, detection of activity outside theinstructions or constraints of the trial can be immediately andautomatically achieved.

1. A dispensing system comprising a programmable dispensing mechanismadapted to receive a sealed container containing multiple doses ofmaterial to be dispensed, and including a mechanical actuation mechanismwhich, when actuated, causes a measured dose of material to be dispensedfrom the container, and wherein the dispensing mechanism is selectivelyinhibited from operation by a locking mechanism which, when actuated,locks the dispensing mechanism against the further dispensing of a doseof material until released in accordance with a desired dispensingprogramme, and wherein the container and dispensing mechanism areprovided with an authenticator to check the authenticity of thecontainer placed in the dispensing mechanism, wherein release of thelocking mechanism is effected by remote control.
 2. The dispensingsystem according to claim 1 wherein release is by the passage ofsufficient time following a previous actuation.
 3. The dispensing systemaccording to claim 1 wherein release is effected by means of a latchingmechanism which acts to lock the dispensing mechanism against dispensinguntil the latching mechanism is released.
 4. The dispensing systemaccording to claim 1 wherein the container has an identification tagassociated therewith and containing information about its content, andthe authenticator of the dispensing mechanism is constructed andarranged to address the tag and validate the dosage regime in accordancewith the dispensing programme.
 5. The dispensing system according toclaim 1 wherein the dispensing mechanism is a hand-held hand-actuateddispensing mechanism including the locking mechanism and a separate baseor docking station, the hand-held dispensing mechanism being constructedand arranged to be placed proximate to the base or docking station inorder to release the locking mechanism.
 6. The dispensing systemaccording to claim 5 wherein the docking or base station is configuredto operate in cooperation with a remote overall control system.
 7. Thedispensing system according to claim 5 wherein the docking or basestation contains a transmitter and a receiver in communication with aremote control computer to exchange data between the remote computer andthe base or docking station when the dispensing mechanism is placed inthe base or docking station.
 8. The dispensing system according to claim7 wherein the dispensing mechanism is configured to upload a dispensinghistory of the hand-held dispensing mechanism to the remote computer inresponse to the remote computer sending the appropriate control signals.9. The dispensing system according to claim 1, wherein the container isresealable.
 10. The dispensing system according to claim 8, wherein thedispensing mechanism uploads the dispensing history at the same time asthe remote computer sends the control signals.
 11. The dispensing systemaccording to claim 8, wherein the dispensing mechanism uploads thedispensing history after the remote computer sends the control signals.12. The dispensing system according to claim 8, wherein the base ordocking station is adapted to receive the control signals.
 13. Thedispensing system according to claim 8, wherein the dispensing mechanismis adapted to receive the control signals.